Implications for Educational Classification and Psychological Diagnoses Using the Wechsler Adult Intelligence Scale–Fourth Edition With Canadian Versus American Norms

• Published in: Journal of psychoeducational assessment Vol. 33; no. 4; pp. 299 - 311
• Main Authors: Harrison, Allyson G., Holmes, Alana, Silvestri, Robert, Armstrong, Irene T.
• Format: Journal Article
• Language: English
• Published: Los Angeles, CA SAGE Publications 01-07-2015
• Subjects: Classification; Clinical Diagnosis; College Students; Differences; Foreign Countries; Intelligence Tests; Learning Disabilities; Mental Retardation; Ontario; Scores; Severity (of Disability); Test Norms; United States; Wechsler Adult Intelligence Scale; Canada; United States; adult; WAIS; normative data; Canadian; intelligence
• ISSN: 0734-2829; 1557-5144
• DOI: 10.1177/0734282915573723

Building on a recent work of Harrison, Armstrong, Harrison, Iverson and Lange which suggested that Wechsler Adult Intelligence Scale–Fourth Edition (WAIS-IV) scores might systematically overestimate the severity of intellectual impairments if Canadian norms are used, the present study examined differences between Canadian and American derived WAIS-IV scores from 861 postsecondary students attending school across the province of Ontario, Canada. This broader data set confirmed a trend whereby individuals’ raw scores systematically produced lower standardized scores through the use of Canadian as opposed to American norms. The differences do not appear to be due to cultural, educational, or population differences, as participants acted as their own controls. The ramifications of utilizing the different norms were examined with regard to psychoeducational assessments and educational placement decisions particularly with respect to the diagnoses of Learning Disability and Intellectual Disability.